The cause of the problem is believed to be the Antilock Braking System (ABS) Hydraulic Control Unit (HCU). Some of the complainants report that after an ABS type braking event--caused by braking on slippery surface, a rough or uneven surface, a manhole cover or similar irregularity in the roadway--the brake pedal goes soft, frequently described as "going to the floor," and the amount of force required by the driver to stop the car increases significantly. In some cases, the driver is unable to stop within their desired stopping distance. Complainants have also reported going past the expected stopping points for stop signs or red lights, and some have reported being out into the flow of traffic before being able to bring the vehicle to a stop.
It is believed that the ABS HCU experiences an internal malfunction which causes an inability to maintain required braking pressure. Reports allege that the condition can continue for some time until it corrects itself, but will then reoccur if another ABS type braking event happens, while other reports indicate that the replacement of the ABS HCU corrects the problem.
ODI has associated three crashes with this condition. A Preliminary Evaluation has been opened to assess the scope, frequency, and safety-related consequence of the alleged defect.